diff mbox series

[v7,4/6] reset: Add Delta TN48M CPLD reset controller

Message ID 20211102165657.3428995-4-robert.marko@sartura.hr
State New
Headers show
Series [v7,1/6] mfd: simple-mfd-i2c: Add Delta TN48M CPLD support | expand

Commit Message

Robert Marko Nov. 2, 2021, 4:56 p.m. UTC
Delta TN48M CPLD exposes resets for the following:
* 88F7040 SoC
* 88F6820 SoC
* 98DX3265 switch MAC-s
* 88E1680 PHY-s
* 88E1512 PHY
* PoE PSE controller

Controller supports only self clearing resets.

Signed-off-by: Robert Marko <robert.marko@sartura.hr>
Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
---
Changes in v5:
* Allow COMPILE_TEST as well
* Default to MFD_TN48M_CPLD

Changes in v4:
* Drop assert and deassert as only self-clearing
resets are support by the HW
* Make sure that reset is cleared before returning
from reset.
---
 drivers/reset/Kconfig       |  10 +++
 drivers/reset/Makefile      |   1 +
 drivers/reset/reset-tn48m.c | 128 ++++++++++++++++++++++++++++++++++++
 3 files changed, 139 insertions(+)
 create mode 100644 drivers/reset/reset-tn48m.c

Comments

Andy Shevchenko Nov. 2, 2021, 7:30 p.m. UTC | #1
On Tue, Nov 2, 2021 at 6:57 PM Robert Marko <robert.marko@sartura.hr> wrote:
>
> Delta TN48M CPLD exposes resets for the following:
> * 88F7040 SoC
> * 88F6820 SoC
> * 98DX3265 switch MAC-s
> * 88E1680 PHY-s
> * 88E1512 PHY
> * PoE PSE controller
>
> Controller supports only self clearing resets.

...

> +#include <linux/device.h>
> +#include <linux/kernel.h>
> +#include <linux/module.h>

> +#include <linux/of.h>

I haven't found any user of this header, but mod_devicetable.h is missing.

> +#include <linux/platform_device.h>
> +#include <linux/regmap.h>
> +#include <linux/reset-controller.h>

> +#include <dt-bindings/reset/delta,tn48m-reset.h>

Shouldn't this go before linux/* as it provides more generic definitions?

...

> +#define TN48M_RESET_TIMEOUT    125000
> +#define TN48M_RESET_SLEEP      10

In which units? (both)
Robert Marko Nov. 5, 2021, 10:24 a.m. UTC | #2
On Tue, Nov 2, 2021 at 8:31 PM Andy Shevchenko
<andy.shevchenko@gmail.com> wrote:
>
> On Tue, Nov 2, 2021 at 6:57 PM Robert Marko <robert.marko@sartura.hr> wrote:
> >
> > Delta TN48M CPLD exposes resets for the following:
> > * 88F7040 SoC
> > * 88F6820 SoC
> > * 98DX3265 switch MAC-s
> > * 88E1680 PHY-s
> > * 88E1512 PHY
> > * PoE PSE controller
> >
> > Controller supports only self clearing resets.
>
> ...
>
> > +#include <linux/device.h>
> > +#include <linux/kernel.h>
> > +#include <linux/module.h>
>
> > +#include <linux/of.h>
>
> I haven't found any user of this header, but mod_devicetable.h is missing.

Hi,
thanks will fix up in v8.

>
> > +#include <linux/platform_device.h>
> > +#include <linux/regmap.h>
> > +#include <linux/reset-controller.h>
>
> > +#include <dt-bindings/reset/delta,tn48m-reset.h>
>
> Shouldn't this go before linux/* as it provides more generic definitions?

I have looked at other drivers and I would say that almost all of them
do it this way,
putting it after other includes.
I also personally prefer it this way.

>
> ...
>
> > +#define TN48M_RESET_TIMEOUT    125000
> > +#define TN48M_RESET_SLEEP      10
>
> In which units? (both)

Its microseconds, will make it clear in v8.

Regards,
Robert
>
> --
> With Best Regards,
> Andy Shevchenko
diff mbox series

Patch

diff --git a/drivers/reset/Kconfig b/drivers/reset/Kconfig
index 5656cac04b4c..e76aba5f4c84 100644
--- a/drivers/reset/Kconfig
+++ b/drivers/reset/Kconfig
@@ -243,6 +243,16 @@  config RESET_TI_SYSCON
 	  you wish to use the reset framework for such memory-mapped devices,
 	  say Y here. Otherwise, say N.
 
+config RESET_TN48M_CPLD
+	tristate "Delta Networks TN48M switch CPLD reset controller"
+	depends on MFD_TN48M_CPLD || COMPILE_TEST
+	default MFD_TN48M_CPLD
+	help
+	  This enables the reset controller driver for the Delta TN48M CPLD.
+	  It provides reset signals for Armada 7040 and 385 SoC-s, Alleycat 3X
+	  switch MAC-s, Alaska OOB ethernet PHY, Quad Alaska ethernet PHY-s and
+	  Microchip PD69200 PoE PSE controller.
+
 config RESET_UNIPHIER
 	tristate "Reset controller driver for UniPhier SoCs"
 	depends on ARCH_UNIPHIER || COMPILE_TEST
diff --git a/drivers/reset/Makefile b/drivers/reset/Makefile
index ea8b8d9ca565..79beab92324f 100644
--- a/drivers/reset/Makefile
+++ b/drivers/reset/Makefile
@@ -31,6 +31,7 @@  obj-$(CONFIG_RESET_SOCFPGA) += reset-socfpga.o
 obj-$(CONFIG_RESET_SUNXI) += reset-sunxi.o
 obj-$(CONFIG_RESET_TI_SCI) += reset-ti-sci.o
 obj-$(CONFIG_RESET_TI_SYSCON) += reset-ti-syscon.o
+obj-$(CONFIG_RESET_TN48M_CPLD) += reset-tn48m.o
 obj-$(CONFIG_RESET_UNIPHIER) += reset-uniphier.o
 obj-$(CONFIG_RESET_UNIPHIER_GLUE) += reset-uniphier-glue.o
 obj-$(CONFIG_RESET_ZYNQ) += reset-zynq.o
diff --git a/drivers/reset/reset-tn48m.c b/drivers/reset/reset-tn48m.c
new file mode 100644
index 000000000000..8b58685f4043
--- /dev/null
+++ b/drivers/reset/reset-tn48m.c
@@ -0,0 +1,128 @@ 
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Delta TN48M CPLD reset driver
+ *
+ * Copyright (C) 2021 Sartura Ltd.
+ *
+ * Author: Robert Marko <robert.marko@sartura.hr>
+ */
+
+#include <linux/device.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/reset-controller.h>
+
+#include <dt-bindings/reset/delta,tn48m-reset.h>
+
+#define TN48M_RESET_REG		0x10
+
+#define TN48M_RESET_TIMEOUT	125000
+#define TN48M_RESET_SLEEP	10
+
+struct tn48_reset_map {
+	u8 bit;
+};
+
+struct tn48_reset_data {
+	struct reset_controller_dev rcdev;
+	struct regmap *regmap;
+};
+
+static const struct tn48_reset_map tn48m_resets[] = {
+	[CPU_88F7040_RESET] = {0},
+	[CPU_88F6820_RESET] = {1},
+	[MAC_98DX3265_RESET] = {2},
+	[PHY_88E1680_RESET] = {4},
+	[PHY_88E1512_RESET] = {6},
+	[POE_RESET] = {7},
+};
+
+static inline struct tn48_reset_data *to_tn48_reset_data(
+			struct reset_controller_dev *rcdev)
+{
+	return container_of(rcdev, struct tn48_reset_data, rcdev);
+}
+
+static int tn48m_control_reset(struct reset_controller_dev *rcdev,
+			       unsigned long id)
+{
+	struct tn48_reset_data *data = to_tn48_reset_data(rcdev);
+	unsigned int val;
+
+	regmap_update_bits(data->regmap, TN48M_RESET_REG,
+			   BIT(tn48m_resets[id].bit), 0);
+
+	return regmap_read_poll_timeout(data->regmap,
+					TN48M_RESET_REG,
+					val,
+					val & BIT(tn48m_resets[id].bit),
+					TN48M_RESET_SLEEP,
+					TN48M_RESET_TIMEOUT);
+}
+
+static int tn48m_control_status(struct reset_controller_dev *rcdev,
+				unsigned long id)
+{
+	struct tn48_reset_data *data = to_tn48_reset_data(rcdev);
+	unsigned int regval;
+	int ret;
+
+	ret = regmap_read(data->regmap, TN48M_RESET_REG, &regval);
+	if (ret < 0)
+		return ret;
+
+	if (BIT(tn48m_resets[id].bit) & regval)
+		return 0;
+	else
+		return 1;
+}
+
+static const struct reset_control_ops tn48_reset_ops = {
+	.reset		= tn48m_control_reset,
+	.status		= tn48m_control_status,
+};
+
+static int tn48m_reset_probe(struct platform_device *pdev)
+{
+	struct tn48_reset_data *data;
+	struct regmap *regmap;
+
+	regmap = dev_get_regmap(pdev->dev.parent, NULL);
+	if (!regmap)
+		return -ENODEV;
+
+	data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	data->regmap = regmap;
+
+	data->rcdev.owner = THIS_MODULE;
+	data->rcdev.ops = &tn48_reset_ops;
+	data->rcdev.nr_resets = ARRAY_SIZE(tn48m_resets);
+	data->rcdev.of_node = pdev->dev.of_node;
+
+	return devm_reset_controller_register(&pdev->dev, &data->rcdev);
+}
+
+static const struct of_device_id tn48m_reset_of_match[] = {
+	{ .compatible = "delta,tn48m-reset", },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, tn48m_reset_of_match);
+
+static struct platform_driver tn48m_reset_driver = {
+	.driver = {
+		.name = "delta-tn48m-reset",
+		.of_match_table = tn48m_reset_of_match,
+	},
+	.probe = tn48m_reset_probe,
+};
+module_platform_driver(tn48m_reset_driver);
+
+MODULE_AUTHOR("Robert Marko <robert.marko@sartura.hr>");
+MODULE_DESCRIPTION("Delta TN48M CPLD reset driver");
+MODULE_LICENSE("GPL");